The National Database of Sources of Environmental Releases of Dioxin-like Compounds in the United States
Note: For more detailed information on the National Database and how to use it, as well as a complete list
of files contained on the CD, please refer to the file titled "userguide.pdf" located in the root directory.

 **Introduction** 
The National Database of Sources of Environmental Releases of Dioxin-like Compounds in the United States has 
been developed by EPA's Office of Research and Development (ORD) to be a repository of congener-specific 
chlorinated dibenzo-p-dioxin/dibenzofuran (CDD/CDF) emission data extracted from original test reports. 
The database was designed to accomodate facility-based emission data, as well as non-facility based sources 
(e.g., mobile sources such as automobiles, and area sources such residential wood combustion).  Test reports
from various State agencies, trade associations, EPA program offices,and EPA regulatory dockets were 
consolidated and assimilated into the database. Most of the emission data in Version 1 of the database
concern releases to air because few data are currently available on releases to other media. The National 
Database consists of approximately 270 spreadsheet files, distributed among 30 directories and subdirectories. 
Each directory/subdirectory contains two types of files: summary files (typically one) and data files.  
The summary file was constructed to provide a consolidated view of the facilities within a particular 
emission source category.  The data files in each directory/subdirectory contain raw data and calculations for 
determining emission factor sEFs) for CDD/CDFs both in chemical units and dioxin toxicity equivalent (TEQ) units.

**Required Hardware and Software**
1. A CD Drive (which you probably have if you are reading this file) 
2. Microsoft Excel Version 5.0 or higher, or Lotus Version 4.0 or higher (for Mac users, the Mac version 
of Excel or Lotus should be able to read the database files) Note: Although there do not appear to be any 
memory constraints in using the CDROM, a computer with a 486 or Pentium processor and an adequate amount of 
RAM (8Mb or higher) should be used in running the CD.

**Getting Started**
After you insert the CD into the CDROM drive, the Nataional Database program should automatically start. 
If your system displays an error message about the file "MSFLXGRD.OCX", follow the instructions below under
**Error Messages**. If the National Database does not automatically start and you are using Windows 95, 98,
or 2000, go to Windows Explorer or My Computer and open the CD. Open the file labelled "DioxinDb.exe" and 
the National Database program should begin. If you are using a system other than Windows 95, 98, or 2000, 
follow the steps outlined below:
	1. Insert the National Database CD into the CDROM drive.
	2. Open Excel or Lotus (see "useguide.pdf" for limitations when using Lotus)
	3. Go to the menu titled File and select Open.
	4. Select the CDROM drive.
	5. Select the appropriate subdirectory of interest.
	6. Select the appropriate file of interest and select Open. As the file opens,Excel will inform the 
	user that the file contains links and will ask the user if they would like to re-establish the links.
	The user should only re-establish the links in a worksheet if they intend to update the worksheet
	with new data and recalculate EFs and TEQs.  The user should be warned that re-establishing links
	may take a few minutes, depending on the speed of their computer.For more information on navigating
	through the CD and for a complete list offiles, see the file titled "userguide.pdf" located in the
	root directory.

**Error Messages**"
Run-time Error 339 Component 'MSFLXGRD.OCX' or one of its dependencies not correctly registered: a file is 
missing or invalid."The file the error is refering to, MSFLXGRD.OCX, is located in the root directory of the
CD.  For most systems, placing the file in this directory does not generate this error.  However, on a few 
computers this error still occurs.  To fix the problem, copy the file to the Windows\System directory on your
hard drive.  The National Database program should then function properly.